Lorentz transformations: how can I derive the time equation?

In summary, starting with the proposition that all observers measure the same value for the speed of light, the geometry setup in which you apply the Pythagorean Theorem is based on the cross-section of the 4-dimensional universe experienced by an observer at some instant of time.
  • #1
TrueBlue1990
4
0
Starting with:

x'=[itex]\gamma[/itex](x-vt) & x=[itex]\gamma[/itex](x'+vt')

I know that I can derive t'=[itex]\gamma[/itex](t-vx/c^2)... however I can't seem to make it fall out mathematically. The suggested method is to cancel x'. Can anyone help me out on the steps?

Much appreciated! :)
 
Physics news on Phys.org
  • #2
Show us how far you've gotten, and maybe someone will give you a nudge from there.
 
  • #3
TrueBlue1990 said:
Starting with:

x'=[itex]\gamma[/itex](x-vt) & x=[itex]\gamma[/itex](x'+vt')

I know that I can derive t'=[itex]\gamma[/itex](t-vx/c^2)... however I can't seem to make it fall out mathematically. The suggested method is to cancel x'. Can anyone help me out on the steps?

Much appreciated! :)



Here is a derivation of time dilation based on the Pythagorean Theorem. It begins with the proposition that all observers measure the same value for the speed of light, regardless of their relative speeds. For this to be true, one picture of such a universe logically includes four dimensions; different observers moving at different constant relativistic speeds relative to each other would be associated with 4-dimensional worldlines slanted with respect to an arbitrarily selected rest frame. An observer's worldline is colinear with his X4 axis along the 4th dimension ("time axis"). Further, the X1 axis is slanted as well, such that the 45-degree photon world line always bisects the angle between X1 and X4 (this assures the same measurement of "c" in all inertial frames)--that's just the way the universe is constructed in four dimensions. In the sketch below, the X1 axes represent the cross-section of the 4-dimensional universe (X2 and X3 are suppressed for ease of viewing) experienced by an observer at some instant of time (some point along the X4 dimension). This sets up the geometry in which you apply the Pythagorean Theorem. In this sketch a blue guy and red guy move in opposite directions at the same relativistic speed relative to the black rest frame. We regard any observer to be moving along his own X4 axis at the speed of light: X4 = ct, or t = X4/c
Four_dimensional_Space.jpg
[/QUOTE]
 
Last edited:

1. What are Lorentz transformations?

Lorentz transformations are mathematical equations used in the theory of special relativity to describe how measurements of space and time change when viewed from different reference frames.

2. Why do we need Lorentz transformations?

We need Lorentz transformations because the laws of physics, specifically the speed of light, are the same for all observers in an inertial reference frame. This means that measurements of space and time must change in a consistent way when viewed from different perspectives.

3. How can I derive the time equation from Lorentz transformations?

The time equation can be derived from Lorentz transformations by using the equations for time dilation and length contraction and substituting them into the Lorentz transformation equation for time. This results in the equation t' = γ(t - vx/c^2), where t' is the time measured in the moving reference frame, t is the time measured in the stationary reference frame, v is the relative velocity between the frames, and c is the speed of light.

4. What is the significance of the time equation in Lorentz transformations?

The time equation is significant because it allows us to calculate the difference in time measurements between two reference frames that are moving relative to each other. This is important in understanding the effects of time dilation and how time is perceived differently by observers in different frames of reference.

5. Are Lorentz transformations only applicable to time measurements?

No, Lorentz transformations are also applicable to measurements of space. The equations for length contraction, which describe how lengths appear shorter in the direction of motion in a moving reference frame, are part of Lorentz transformations. The time and space equations are used together to describe the complete transformation of space and time measurements between reference frames.

Similar threads

  • Special and General Relativity
2
Replies
54
Views
1K
  • Special and General Relativity
Replies
10
Views
598
  • Special and General Relativity
3
Replies
101
Views
3K
  • Special and General Relativity
Replies
22
Views
1K
  • Special and General Relativity
Replies
13
Views
1K
  • Special and General Relativity
Replies
24
Views
2K
  • Special and General Relativity
Replies
33
Views
2K
  • Special and General Relativity
Replies
20
Views
1K
  • Special and General Relativity
Replies
30
Views
2K
  • Special and General Relativity
Replies
14
Views
217
Back
Top